High performance fastener assembly lube allows engine builders to torque fasteners to their required preload on the first pull.

Because of frictional inconsistencies with oil, moly, and other substances employed by engine builders, when a fastener is tightened to the desired level of torque it typically does not stretch the required amount to reach the proper preload and the torque wrench “clicks” prematurely. It takes multiple cycles of torquing the bolt, loosening it and tightening it again to obtain the required preload. This phenomenon is called “preload scatter.” With ARP Ultra-Torque, a fastener need only be torqued once to get within 5% of ideal preload —and remains consistent through all subsequent cycles (from race-prep machining through final assembly). Moreover, given the inconsistencies of ordinary lubes, it is quite possible for adjacent head bolts or studs to have vastly different preloads. This “scatter” causes bore distortion, hampers piston ring seal, and leads to poor head gasket sealing. Preload differences in connecting rods and main caps can cause uneven bearing loading.